ERROR: MWCS: dimension mismatch (mw_open)

coelho · Joined: 19 Mar 2007 Posts: 1

Hi Everybody

Please, I can't open a fits file with IRAF (v 2.12). I
received the following error message :
cl> splot eohi079.fits
cl > ERROR: MWCS: dimension mismatch (mw_open)

Thank you

valdes · IRAF Guru Joined: 11 Nov 2005 Posts: 676

Hi,

This is a common error message with spectra. What it means is that the WCS is 2D where the axes are coupled. This usually is the result of having a celestial WCS; i.e. an RA/DEC WCS. See

http://iraf.net/phpBB2/viewtopic.php?t=84378

For a previous reply.

Yours,
Frank Valdes

bgandersson · Joined: 27 Mar 2011 Posts: 3 Location: SOFIA/USRA

fitz · Posted: Mon Mar 28, 2011 5:50 am Post subject:

See both of:

http://iraf.net/phpBB2/viewtopic.php?t=90476
http://iraf.net/phpBB2/viewtopic.php?t=90345

If neither of these explains your problem please post a sample image to the anonftp at ftp://iraf.noao.edu/pub

bgandersson · Joined: 27 Mar 2011 Posts: 3 Location: SOFIA/USRA

So, I think the "dimension mismatch" is a red herring, and that likely the issue if something with priv.s and directory structures, since if I try to plot a 1D spectrum I get a

mscred> splot BGAnd_spclass_new.imh
ERROR: Cannot open image (BGAnd_spclass_new.imh)

while if I try to plot a line from a multi-dimentsional image I get

mscred> splot ALrj070066.imh
ERROR: MWCS: dimension mismatch (mw_open)

What I did was to replace the /iraf/iraf directory structure with the v2.15 binaries, but leaving /iraf/imdirs intact. I checked the login.cl file and the pointer to imdirs is correct. If I restore the v2.13 structure, from backup, things work fine again (but of course that means I don't have the up-to-date version) So it seems I'm breaking some link or resetting some access privilege by inserting the v2.15 binaries somehow.

I've checked the owner and privileges on the directory and they look OK.

What am I missing?

fitz · Posted: Thu Mar 31, 2011 6:13 pm Post subject:

I hope you're not saying you installed only the v2.15 binaries ?? If there are permission or header problems it would be with the image files, not the iraf installation, however you definitely need to do a full install of IRAF and not just update the binaries.

Otherwise, it would help if you could upload the image or at least post an image header.